Percussion tool



April 26, 1949. v. 1.. PRICE 23,104

PERCUSSION TOOL Y Original Filed Oct. 24, 1942 I 2 Sheets-Sheet l F1|5 J F1 E I IN V EN TOR. Var/70x7 4. PM be BY I A ril 26, 1949. Y mm: Re. 23,104

' PERCUSSION TodL Original Filed Oct. 24, 1942 2 Sheets- Sheet 2 U f V INVENTOR. V6/770/7 Afr/ca BY Arm/2min;

ileiu'ued Apr. 26, 1949 UNITED STATES. PATENT OFFICE Serial No. 463,275, October .24, 1942. Application for reissue February 23, 1949, Serial No.

- This invention relates to percussion tools and more particularly to cradle or shell mounted type. In general, these devices utilize a fluid actuated percussive tool, within which a hammer piston is adapted to reciprocate, to drive a drill or other implements. Usually they are fixed on a frame and include a handle means for directing or guiding the assembly.

It is one of the principal objects of this invention to provide a percussion tool which will materially reduce, if not entirely eliminate, vibration usually transmitted to the operator through the handle or grip means.

It is an object of this invention to eliminate unnecessary vibration by providing a direct connection between handle or grip means and the tool to be driven whereby the vibration may be dissipated instead of transmitted to the operator.

Additionally, it is an object of the invention to provide a device in which a positive grip is maintained. on the bit or other tool while utilizing a "floating hammer means.

These and other objects of the invention will become more apparent as this specification proceeds and the novelty of the invention will be pointed out with the requisite degree of particularity in the appended claims.

In the drawings forming a part hereof wherein three preferred embodiments of the invention are shown:

Figure 1 is a front elevation of a percussion tool,

Figure 2 is a side elevation of the subject matter of Figure 1,

Figure 3 is a section along the line 3-3 of Figure 2,

Figure 4 is a section along the line 44 of Figure 2,

Figure 5 is a side elevation of a second percussion tool, and

Figure 6 is a front elevation of a third embodiment of the invention,

In the case of the known and conventional percussion tools of the heavy duty type, such as are used in demolition and construction work and in mining operations, there has been a justifiable, universal complaint that use of the devices worked unnecessary physical hardship on the operators due to excessive vibrations transmitted through the entire structures. This has been due to'the fact that heretofore the tools have included fixed connections between the handles and the percussive means, as a. result of which the vibratory motion attendant upon each stroke of the air piston is communicated through the trame members to the handles and thence to the 3 Claims. (01. 255-51) .operator. The provision of spring connections between handle and air hammer has reduced in a minor degree only the unnecessary transmission of such vibrations.

The present invention contemplates the use of .a frame member, having a handle on one end and a tool retainer on the other, as a stationary support *for the fluid actuated percussive means, the connection between the two permitting vibratory reciprocation of the percussive means. In other Words, the present invention proposes the gripping oi the tool to be struck, as in the case of a hand held drill, rather than the gripping of the percussive member. Consequently, the only motion transmitted to the handle means will be the minute longitudinal movement of the tool under impact of the percussive member while re ciprocal vibratory motion of the percussive member will be, insofar as the operator is concerned, dissipated in the connection between percussive member and its supporting frame.

Referring to Figures 1 to 4 of the drawings th numeral l0 designates a frame member in the form of a single rod bent inwardly at its bottom end, as at H, to form a part of a tool retainer and bent outwardly at its upper end, as at I2, to-

accommodate the enlarged head I3 on the casing of a percussive member M, with which it is connected. At its extreme upper end the frame In is provided with a handle l8 having a neck portion l9 to center the handle over the percussive member I l. The neck portion i9 may be connected to the upper end of frame rod in by means of the bolts 2| or it may be an integral part of the rod III, as preferred.

The connection between the percussive member l4 and rod I0 is reciprocal in character and in the form shown in Figures 1 to 4, inclusive, the upper end l2 of rod I0 is flattened out for a portion of its length (see Figures 1 and 3) and provided with a longitudinally extending guideway 25 to slidably receive a flange 26 projecting laterally from head l3 on percussive member I. This slidable connection permits dissipation of the extreme vibration of the percussive member [4 when actuated by the usual compressed air stream.

The percussive member II is of conventional design and includes an air intake line 21 communicating with its upper end, the supply of air being controlled by a throttle valve for which a grip lever 28 is provided in handle l8. flexible connection 28 between lever 28 and the throttle valve (not shown) consists of a conventional cable-sheathed relatively still but bendable The wire (see Fig. of the type commonly employed for remote control of valves, such as the automobile choke control. Such flexible connection 29 is in keeping with the reciprocal connection between the percussive member I 4 and frame rod l0, constituting an operating connection between said control. lever 28 and the: throttle valve in all positions to. which the percussivehammer mechanism may slide on the frame rod Ill. The percussive member I4 additionally has an exhaust 101 port 30 and is chambered at its lower end in the usual way to receive a standard drill bit 31". It will be appreciated, of course, that the presentinvention is not concerned with the internal construction of the percussive niemberandxinasmuch" as these devices are well linown imthe ar't' n" details thereof are deemed necessary inthe drawings or this description.

The lower end ll of rod ID, as stated, is bent inwardly to form a portion of a retainer for the bit 3|. In Figure 4 the particular shape of that part of the retainer which is integral withrod I0 is shown to best advantage aslconforming. to the cross-section of one-half of the bit 31, while a detachable complemental piece 32 forms the other half of the retainer means. The detach able piece. 32 is secured to the end portion ll of rod' l0by conventional means such as the boltsv 33" and nuts 34L To provide a positive grip on bit 3| a. renewable. bushing 35 of rubber or the 30 like material. is inserted between the bit. 3| and the retainer means, namely..- the end H of rod lfl andIthe detachable member 32.

In the form shown in Figure S-the. percussive member I4 is supported for reciprocal vibratory 5 movementv on a frame. having. substantially the same shape as rod Illin Figure 1 and. provided with the same. drill bit retainer atitsrlowerend including the detachable piece 32. Inthisform the connection. between the: percussive member l4 andframe 4'0 consists in a pin .42 projecting downwardly througha bore-43 inthe inwardly bent upper endifl of:framefill,which pini 42 is slidably receivedby a sleeve 45 formed inf tegral withandprojecting upwardly: from vhead 45 46:ofpercussivemember- I 4.- Pin 42 may be. adjusted relative-to thesleeve45 by meansofa set; screw 41 entering. bore 43. A conventional handle 48 is formed on the upper. end ofpin; 42 as a matter of simplifyingthe. structure and: 50 the handle carriesthe usualthrottle valve control lever t9. I

In 7 the form illustrated" in Figure :6 the percussive member 14 is supported onaU-shapedirame member ESthelegs-of which aredeformedatthe pointof their. connection-to provide-.pne-half of a-bit retainer 56,the-o ther half of .whichlma y beadetachable. piece 51 and, like -the piece. 32 of Figure 4,: secured thereto by bolts w 58-: The-legs of the frame member- 55- are parallel for the 60 greaterportion of their length but fiared out wardly at their? upper ends; as-at-5-9 to accom modate the en-larged :head '60 of. percussive mem here; The frame assemblyflis completed by 91* crosslhandletfi'lihaving mes '62 bywhlch it'israt tached to the upper ends of the frame" legs through the medium of cap-screws? Tliefislidable-connecticn between percussive" member-H and frame 5iiinthe deviceof Figure fi comprlses 7 guideways=68 in-the-upper ends of-th'e' two legs 4 of the frame receiving oppositely projecting flanges 63 on head 60.

In the three forms of the device shown in the drawings and described herein, it will be appreciated that the connections between the handle, frame and drill bit are rigid while the percussive member has a floating connectiontd the frame member; In: this-way the vibratory motion of the percussive member is dissipated in the sliding connection of hammer and frame and the only mction transmitted from the percussive member to the bit, and hence to the frame and handle assembly, will be the repeated impact of the percussive member on the drill. Such construction: will not" only avoid constant personal discomforture to the operator but will provide a more positive control of the bit or other tool and enablethe operator to operate the same with increased efficiency.

While I have shown and described butthree forms of-=the invention itwill l e-appreciated that the principles thereof; may be incorporated in otherdevices, and I therefore desire full protection withinthe spirit and scope ofthe appended claims.

The invention-claimed-is;

1. A percussion tool of the'shell mounted type comprising a frame member, a-handleon the" upper end' of the-frame'membe gsamemberP jecting downwardly fromthe handle portion of theframe,- a positive grip tool retainer means carried by the lower endof the-fra1ne,saspercuse sive means supported on a tool grippedby the retainer meansan upwardly projecting: sleevemember on thepercussive means toreceive themember projecting downwardl portion of the frame.

2.-A percussion tool comprising a= frame} a handle on said frame, atool retainer on' said frame, percussive hammer mechanismslidably y from thehandle supported on said frame'for"percussivecontactwith a toolretainedby saidtool-retainer; said percussive hammer mechanismincluding: a-- throttle valve, a throttle valve"control member carried by. said handle anda flexible-connec tion between said control member" and said throttle valve.

3: A percussion-tool comprising a framepa han dle on said frame, a tool retainer on said framei percussive hammer mechanism-- slidably-=- supported on said frame for percussive contactiwith a tool retained by said tool retainer; said-percus sive hammer mechanism: including; a} throttle valve, a throttle valve control member carried said 1 handle; and means constituting an operating connection between said control member and said throttle valvein all positions to which "said percussive hammer mechanism may slide orr'saidframe. I i VERNON *L; PRICE.

REFERENciis oH iin UNITED STATES PlATEN I 

